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- *****************************************************************************
- * Alanine dehydrogenase and pyridine nucleotide transhydrogenase signatures *
- *****************************************************************************
-
- The following dehydrogenases have been shown [1] to share regions of
- similarity:
-
- - Alanine dehydrogenase (EC 1.4.1.1), an enzyme which catalyzes the NAD-
- dependent reversible reductive amination of pyruvate into alanine.
- - Pyridine nucleotide transhydrogenase (EC 1.6.1.1), which is the enzyme that
- catalyzes the reduction of NADP+ to NADPH with the concomitant oxidation of
- NADH to NAD+. This enzyme is located in the plasma membrane of prokaryotes
- and in the inner membrane of the mitochondria of eukaryotes. The
- transhydrogenation between NADH and NADP is coupled with the translocation
- of a proton across the membrane. In prokaryotes the enzyme is composed of
- two different subunits: an alpha chain (gene pntA) and a beta chain (gene
- pntB) while in eukaryotes it is a single chain protein.
-
- The sequence of alanine dehydrogenase from several bacterial species are
- related with those of the alpha subunit of bacterial pyridine nucleotide
- transhydrogenase and of the N-terminal half of the eukaryotic enzyme. The two
- most conserved regions correspond respectively to the N-terminal extremity of
- these proteins and to a central glycine-rich region which is part of the
- NAD(H)-binding site. We have developed signature patterns for both regions.
-
- -Consensus pattern: G-[LIVM]-P-x-E-x(3)-N-E-x(1,3)-R-V-A-x-[ST]-P-x-[GST]-V-
- x(2)-L-x-[KRH]-x-G
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: [LIVM](2)-G-[GA]-G-x-A-G-x(2)-[SA]-x(3)-[GA]-x-[SG]-
- [LIVM]-G-A-x-V-x(3)-D
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: October 1993 / First entry.
-
- [ 1] Delforge D., Depiereux E., de Bolle X., Feytmans E., Remacle J.
- Biochem. Biophys. Res. Commun. 190:1073-1079(1993).
-